document.write( "Question 1169600: How many liters of pure alcohol must be added to 15 liters of 20% solution to obtain a mixture which is 30% alcohol \n" ); document.write( "
Algebra.Com's Answer #794381 by ikleyn(52790)\"\" \"About 
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document.write( "Let V be the volume of the pure alcohol to add.\r\n" );
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document.write( "Then the volume of the 30% mixture is (15+V) liters, and you have this equation \r\n" );
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document.write( "    0.2*15 + V = 0.3*(15+V).    (1)\r\n" );
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document.write( "It says that the pure alcohol amount in ingredients (left side) us the same as the alcohol amount in the final mixture (right side).\r\n" );
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document.write( "From this equation, you have\r\n" );
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document.write( "    0.2*15 + V = 0.3*15 + 0.3V\r\n" );
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document.write( "    V   - 0.3V = 0.3*15 - 0.2*15\r\n" );
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document.write( "    V = \"%280.3%2A15+-+0.2%2A15%29%2F0.7\" = 2.143 liters (approximately).\r\n" );
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document.write( "CHECK.  I will check equation (1):  \r\n" );
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document.write( "        Left side  is  0.2*15 + 2.143 = 5.143 liters of the pure alcohol;\r\n" );
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document.write( "        Right side is  0.3*(15+2.143) = 5.143 liters of the pure alcohol.\r\n" );
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document.write( "              ! Precisely correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "In this site, there is entire bunch of lessons covering various types of mixture problems\r
\n" ); document.write( "\n" ); document.write( "    - Mixture problems\r
\n" ); document.write( "\n" ); document.write( "    - More Mixture problems\r
\n" ); document.write( "\n" ); document.write( "    - Solving typical word problems on mixtures for solutions \r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for antifreeze solutions \r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for dry substances like coffee beans, nuts, cashew and peanuts\r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for dry substances like candies, dried fruits\r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for dry substances like soil and sand\r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for alloys \r
\n" ); document.write( "\n" ); document.write( "    - Typical word problems on mixtures from the archive\r
\n" ); document.write( "\n" ); document.write( "    - Advanced mixture problems \r
\n" ); document.write( "\n" ); document.write( "    - Advanced mixture problem for three alloys \r
\n" ); document.write( "\n" ); document.write( "    - Unusual word problem on mixtures \r
\n" ); document.write( "\n" ); document.write( "    - Check if you know the basics of mixtures from Science \r
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\n" ); document.write( "\n" ); document.write( "    - Special type mixture problems on DILUTION adding water\r
\n" ); document.write( "\n" ); document.write( "    - Increasing concentration of an acid solution by adding pure acid \r
\n" ); document.write( "\n" ); document.write( "    - Draining-replacing mixture problems \r
\n" ); document.write( "\n" ); document.write( "    - How much water must be evaporated \r
\n" ); document.write( "\n" ); document.write( "    - Advanced problems on draining and replacing \r
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\n" ); document.write( "\n" ); document.write( "    - OVERVIEW of lessons on word problems for mixtures\r
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\n" ); document.write( "\n" ); document.write( "A convenient place to quickly observe these lessons from a  \"bird flight height\"  (a top view)  is the last lesson in the list.\r
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\n" ); document.write( "\n" ); document.write( "Read them and become an expert in solution the mixture word problems.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Mixture problems\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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